In the context of applications running in a client server environment, there is often a need to convert structured business data from an internal server side format into an external client side format for read scenarios, and vice versa for write scenarios. Note that there are different consumption scenarios on the client side (e.g. for mobile devices or Web UIs) which have an impact on the structure of the requested business data by the client (e.g. complex hierarchically structured server-side data that is supposed to be displayed on devices with limited graphical functionality).
Simple examples include conversion of time/date information, or conversion of currencies. More complex conversions have to be done for table-like structures or hierarchical (deep nested) structures, which have a proprietary internal format on the server side, and are to be converted into one or more various external formats like RSS, XML, JSON or ODATA for client side consumption.
Current server applications expose the data values of structured business data in one fixed format, which might not meet the requirements of certain clients. A common solution to this problem is to implement some logic in the client to adjust this data format to a desired format.
With the present emergence of cloud based technologies and mobile business scenarios with short innovation cycles, there is a need for a decoupling of the core service implementations from the client side consumption of business data. Thus, there is a growing need to shift control over the data format into the service calls, and to enable different clients to be configured differently to be able to consume the services directly without any adjustments.